When embryosac receives two or more than two pollen tubes the sperm nucleus fusing with the egg nucleus may be derived from one pollen tube and one fusing with the polar nuclei may be derived from other pollen tube, the phenomenon is termed as

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Answer :

When embryosac receives two or more than two pollen tubes the sperm nucleus fusing with the egg nucleus may be derived from one pollen tube and one fusing with the polar nuclei may be derived from other pollen tube, the phenomenon is termed as – Heterofertilization

Related questions

Description : Double fertilisation is fusion of (a) two eggs (b) two eggs and polar nuclei with pollen nuclei (c) one male gamete with egg and other with synergid (d) one male gamete with egg and other with secondary nucleus.

Last Answer : (d) one male gamete with egg and other with secondary nucleus.

Description : Double fertilisation is (a) fusion of two male gametes of a pollen tube with two different eggs (b) fusion of one male gamete with two polar nuclei (c) fusion of two male gametes with one egg (d) syngamy and triple fusion.

Last Answer : (d) syngamy and triple fusion.

Description : Double fertilization is (1) Fusion of two male gametes of a pollen tube with two different eggs (2) Fusion of one male gamete with two polar nuclei (3) Fusion of two male gametes with one egg (4) Syngamy and triple fusion

Last Answer : (4) Syngamy and triple fusion

Description : Formation of 8-nucleate embryosac by pollen grains is also called as

Last Answer : Formation of 8-nucleate embryosac by pollen grains is also called as – Nemec phenomenon 

Description : Egg cell without synergids is found in embryosac of

Last Answer : Egg cell without synergids is found in embryosac of – Plumbagella type

Description : What are the cells found in the egg apparatus of matured embryosac?  

Last Answer : Ans: Two synergids and one egg cell  

Description : In a cell haploid chromosome number is 15. What number is found in Pollen grain, Zygote, Primary endosperm nucleus and Colchicine treated zygote. 

Last Answer : Ans: 15 in pollen grain, 30 in zygote, 45 in Primary Endosperm nucleus and 60 in colchicine treated zygote.

Description : Formation of diploid embryosac from diploid vegetative structure, e.g., nucellus or integument etc., without meiosis is called: (a) Apospory (b) Apomixis (c) Diplospory (d) Adventives polyembryony

Last Answer : Ans. ((a))

Description : When the diploid embryosac is formed from the cells of nucellus, it is known as

Last Answer : When the diploid embryosac is formed from the cells of nucellus, it is known as – Apospory

Description : When a diploid embryosac is formed from a megaspore mother cell without meiosis, it is called as

Last Answer : When a diploid embryosac is formed from a megaspore mother cell without meiosis, it is called as – Diplospory

Description : When multiple embryo develop from different embryosac it is called as

Last Answer : When multiple embryo develop from different embryosac it is called as – False polyembryony

Description : Nucellus and embryosac both are curved in – 

Last Answer : Nucellus and embryosac both are curved in – Amphitropus ovule

Description : The most common type of embryosac in Angiosperms is

Last Answer : The most common type of embryosac in Angiosperms is – Polygonum type

Description : When the embryo develops from haploid egg cell without fertilization, the phenomenon is called as

Last Answer : When the embryo develops from haploid egg cell without fertilization, the phenomenon is called as – Haploid parthenogenesis

Description : Sperm and egg nuclei fuse due to (a) base pairing of their DNA and RNA (b) formation of hydrogen bonds (c) mutual attraction due to differences in electrical charges (d) attraction of their protoplasts.

Last Answer : attraction of their protoplasts

Description : What is the fate of the male gametes discharged in the synergid? (a) One fuses with the egg and other fuses with central cell nuclei. (b) One fuses with the egg, other(s) degenerates in the synergid. (c) All fuse with the egg. (d) One fuses with the egg, other(s) fuse(s) with synergid nucleus.

Last Answer : (a) One fuses with the egg and other fuses with central cell nuclei.

Description : The phenomenon of nuclear fusion of sperm and egg is known as :

Last Answer : The phenomenon of nuclear fusion of sperm and egg is known as : A. Karyogamy B. Parthenogenesis C. Vitellogenesis D. Oogenesis

Description : Assertion : When sperm enters in egg , one polar body is released in human . Reason : At the time of ovulation eggs found in secondary Oocyte phase .

Last Answer : Assertion : When sperm enters in egg , one polar body is released in human . Reason : At the time ... False . D. If both Assertion & Reason are False.

Description : Extrusion of second polar body from egg occurs (a) simultaneously with first cleavage (b) after entry of sperm but before fertilisation (c) after fertilisation (d) before entry of sperm into ovum.

Last Answer : (b) after entry of sperm but before fertilisation

Description : In double fertilization, the two male nuclei fuse with

Last Answer : In double fertilization, the two male nuclei fuse with – Egg cell and Definitive nucleus

Description : What does the filiform apparatus do at the entrance into ovule? (a) It brings about opening of the pollen tube. (b) It guides pollen tube from a synergid to egg. (c) It helps in the entry of pollen tube into a synergid. (d) It prevents entry of more than one pollen tube into the embryo sac

Last Answer : (b) It guides pollen tube from a synergid to egg.

Description : On fertilization of egg nucleus with sperm nucleus

Last Answer : On fertilization of egg nucleus with sperm nucleus A. Second maturation is completed B. Embryo is ... body is formed D. First maturation is completed.

Description : Every multicellular organism, be it a microscopic alga, a banyan tree or a human being, starts as a single cell called a/an (a) Egg (b) Sperm (c) Nucleus (d) Gene

Last Answer : Ans:(a)

Description : In an egg, the type of cleavage is determined by (a) the amount and distribution of yolk (b) the number of egg membranes (c) the shape and size of the sperm (d) the size and location of the nucleus.

Last Answer : (a) the amount and distribution of yolk

Description : In angiosperms, pollen tube liberate their male gametes into the (a) central cell (b) antipodal cells (c) egg cell (d) synergids.

Last Answer : d) synergids.

Description : Through which cell of the embryo sac, does the pollen tube enter the embryo sac? (a) Egg cell (b) Persistant synergid (c) Degenerated synergids (d) Central cell

Last Answer : c) Degenerated synergids

Description : In gymnosperms, the pollen chamber represents (a) a cavity in the ovule in which pollen grains are stored after pollination (b) an opening in the megagametophyte through which the pollen tube approaches the ... pollen grains develop (d) a cell in the pollen grain in which the sperms are formed.

Last Answer : (c) the microsporangium in which pollen grains develop

Description : The second maturation division of the mammalian ovum occurs (a) shortly after ovulation before the ovum makes entry into the fallopian tube (b) until after the ovum has been penetrated by a sperm ... with that of the ovum (d) in the Graafian follicle following the first maturation division.

Last Answer : (b) until after the ovum has been penetrated by a sperm

Description : In hybridization this is not part of the technique used a) Transfer pollen b) Collect pollen c) Emasculate d) Use of two plants to bridge the stems together 

Last Answer : d) Use of two plants to bridge the stems together

Description : Explain "Shimal Animal Pollen Flower" ?

Last Answer : Animal flowers are usually fairly large. However, even though it is small, the flowers are decorated with inflorescences. Their colors are attractive. All these flowers may or may not have an odor. As these features are present in Shimul flower, Shimul flower is also an animal flower.

Description : In angiosperm, triple fusion is necessary for the formation of: (a) Embryo (b) Pollen (c) Endosperm (d) Leaf

Last Answer : Ans. ((c))

Description : Haploid cells belong to: (a) Integument, pollen grain, endosperm (b) Embryo, endosperm and pollen grain (c) Megaspore, pollen grain, antipodal (d) Integument, pollen grain and antipodal

Last Answer : Ans. ((c))

Description : The process involving emasculation of the flower before anthesis and depositing pollen grains on the cut end of the ovary is called as

Last Answer : The process involving emasculation of the flower before anthesis and depositing pollen grains on the cut end of the ovary is called as – Intra-ovarian pollination

Description : Effect of pollen grains on the properties of endosperms is called as

Last Answer : Effect of pollen grains on the properties of endosperms is called as – Xenia

Description : Very long pollen with needle shaped structures are found in

Last Answer : Very long pollen with needle shaped structures are found in – Zostera

Description : Before, germination of pollen, the moisture necessary for pollen hydration is provided by

Last Answer : Before, germination of pollen, the moisture necessary for pollen hydration is provided by – Stigma

Description : In Angiosperms, during pollination, the pollen grains are mostly

Last Answer : In Angiosperms, during pollination, the pollen grains are mostly – Bicellular

Description : Pollen embryoids were first developed by

Last Answer : Pollen embryoids were first developed by – Guha and Maheshwari

Description : Pollen grains of angiosperms are

Last Answer : Pollen grains of angiosperms are – Partially developed male gametophyte

Description : What is meant by Monosiphonous and Polysiphonous pollen grains? Give examples. 

Last Answer : Ans: Pollen gains that form single pollen tube are monosiphonous. Ex: Solanum. Which form more than one pollen tubes are Polysiphonous. Ex: Malvaceae, Cucurbitaceae 

Description : What is the sign of sperm ?

Last Answer : : The sign of sperm is: C6 H12 O6

Description : If a sporangium derived from a single cell is called (a) Leptosporangiate (b) Eusporangiate (c) Heterosporangiate (d) None of the above

Last Answer : Ans. ((a))

Description : The word 'Agriculture' is derived from— a) Greek b) Latin c) Arabic d) French 

Last Answer : b) Latin

Description : When anther and stigma mature at different time, this phenomenon is called as

Last Answer : When anther and stigma mature at different time, this phenomenon is called as – Dichogamy

Description : Classical taxonomy is also termed a) Beta taxonomy b) Systematic c) Descriptive taxonomy d) Experimental taxonomy

Last Answer : a) Beta taxonomy

Description : The opening into the vagina on the perineum is termed the a) introitus. The introitus is the vaginal orifice. b) adnexa. Adnexa is a term used to describe the fallopian tubes and ovaries ... The hymen is a tissue that may cover the vaginal opening partially or completely before vaginal penetration.

Last Answer : a) introitus. The introitus is the vaginal orifice.

Description : Consider the following statement: (1) In plant cells, cytokinesis start with the formation of the phragmoplast (2) Phragmoplast comprises intrazonal microtubules and Golgi vesicles (3) Primary cell wall is produced by microtubules (4) Phragmoplast is formed by nucleus

Last Answer : Ans. ((a))

Description : Organelles involved in photorespiration are (a) Mitochondria, chloroplasts and ribosomes (b) Mitochondria, Peroxisomes and chloroplasts (c) Mitochondria, nucleus and ribosomes (d) Mitochondria, proxisomes and glyoxisomes

Last Answer : Ans. ((b))

Description : Endoplasmic reticulum remain in continuation with: (a) nucleus (b) Ribosomes (c) Mitochondria (d) Golgi bodies

Last Answer : Ans. ((a))

Description : Which one is common amongst nucleus, chloroplast and mitochondria? (a) Cristae (b) Thylakoids (c) Nucleic acid (d) Carbohydrate metabolism

Last Answer : Ans. ((c))